This invention relates to an improved roll-up shutter formed of horizontally elongated slats which are pivotally connected together along their upper and lower edges. The improvement relates to shutter edge connections which provide reinforcing, bar-like strips extending along the width of the shutter to resist penetration by forcefully hurled objects.
Roll-up shutters are conventionally made of relatively thin, narrow, horizontally elongated slats which are connected together along their adjacent edges. Typically, these slats are formed of aluminum or plastic extrusions. In such extrusions, the body of each slat is formed in a roughly rectangular cross-sectional shape to provide a hollow interior. The upper edge of each slat is provided with a hook-like bend which fits into a channel formed in the lower edge of the next adjacent slat for pivotally connecting the two slats together.
When the shutter is opened, so that the slats are in a generally vertical plane for providing a closure, each slat is suspended from the slat next above it by the connection of their respective hook bends and channels. The shutter is rolled-up, around an axis, which may be in the form of an interior axle or shaft, so that the adjacent slats pivot relative to each other during the rolling procedure.
Roll-up shutter slats as described above are common and generally operate on the same principle. The cross-sectional shapes of the slats may vary from one shutter to another. Also, conventional slats, which are usually formed in a hollow box-like cross-section, may contain interior reinforcing ribs or other interior structures for rigidifying each slat to some extent.
Although these conventional roll-up type shutters are relatively strong, they are susceptible to penetration or breakage if a sufficiently forceful impact is applied against them. That is, a rapidly moving object, such as wind-hurled debris thrown by a high-velocity, hurricane force winds, might penetrate or break apart the shutter, particularly at the connections between its slats. Thus, it is desirable, especially in areas which are subject to hurricane strength winds where wind-hurled objects are a danger, to provide a means for reinforcing each shutter to resist penetration by such flying objects.
The invention herein relates to an improved slat connecting pivot configuration which functions to provide reinforcing strips along the width of the shutter.